snoop Command Modifications
for IPv6 Support

The snoop command can capture
both IPv4 and IPv6 packets. This command can display IPv6 headers, IPv6 extension
headers, ICMPv6 headers, and Neighbor Discovery protocol data. By default,
the snoop command displays both IPv4 and IPv6 packets.
If you specify the ip or ip6 protocol
keyword, the snoop command displays only IPv4 or IPv6 packets.
The IPv6 filter option enables you to filter through all packets, both IPv4
and IPv6, displaying only the IPv6 packets. See the snoop(1M) man page for details. See How to Monitor IPv6 Network Traffic for procedures
that use the snoop command.